Remote control system



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2 3%@ J. M. PEUKAN REMOTE CONTROL SYSTEM Filed Jan.. 27, 1932 Patented pr.

UITED STATES PATENT OFFICE REMOTE CONTROL SYSTEM Application January 27, 1932, Serial No. 589,182

S Claims.

My invention relates to remote control systems of the type comprising a central olce and a plurality of line stations connected by a line circuit over which codes are transmitted for the purpose of communicating intelligence between the several stations and the oiiice.

In systems of the type described, it is customary to carry the line circuit through the several stations in series` and it follows that in the absence of preventative means, should a fault occur in the line circuit, the entire system would be disabled. In accordance with my present invention, I propose to provide means for automatically locating the position ci a fault and for shunting the line circuit on the oiiice side of such fault so that the portion of the system between the central oiiice and the last station on the: oice side of the fault is available for normal operation.

The system of my invention operates in such a manner that the available portion of the line circuit is restored automatically after the occurrence of a fault, and is an improvement upon the system disclosed in an application for Letters Patent of the United States, Serial No. 549,589, filed by G. W. Baughman, on July 9, 1931, for Remote control' systems.

In at least one form of remote control system which has been proposed, the communication between the office and the several stations is accomplished by means of codes which are formed by periodically interrupting the normally closed line circuit. In practicing my invention, I provide at each station a fault relay arranged to be operated if the line circuit is open for a time interval l longer than the greatest period of open circuit normally occurring during code transmission. When these fault relays are operated, the line circuit is sectionalized at each station, and automatic means then become effective to remove the shunt at the several stations in order, commencing at the station nearest the ollice and continuing until the last station on the ofce side of the break is reached. With this arrangement the line circuit is available for use up to the last station on the ofce side of the break and I also provide means for indicating at the office when a break occurs in the line circuit and also when the apparatus has restored the line circuit up to the point of the break.

I will describe two forms of apparatus embodying my invention, and will then point out the novel features thereof in claims. l

In the accompanying drawing, Fig. 1 is' a diagrammatic vieW illustrating one form of remote control system embodyingv my invention. Fig. 2

is a detail view showing a modified form of a portion of the apparatus illustrated in Fig. 1, Figs. 3 and' 4 illustrate details of the station apparatus of the system of Fig. 1.

Similar reference characters refer to similar 5 parts in all views.

Referring first to Fig. 1, I have shown a remote control system comprising a despatchers oil'ice and a plurality of line stations connected by a line circuit including line wires DI and D2. Only two line stations are illustrated complete in the drawing, it being understood that any reasonable number of stations can be controlled over a single line circuit.

The line circuit is normally closed and includes a source of energy, such as a battery N, which as here shown, is located at the oice, and a plurality of line relays one located at the ofiice and one at each station and all connected in series in the line circuit. Each line relay is designated by the ref- 2O erence character R with a prei-lx corresponding to the location. I also provide the oflice and each staion with a transmitter relay designated by the reference character T with an appropriate distinguishing preiix and equipped with a back` contact I included in the line circuit. The transmitter relays may be operated selectively by means forming no part of the present disclosure to interrupt the line circuit in accordance with distinctive codes, thereby causing the line relays R to operate in accordance with these codes. It is customary to provide code receiving means controlled by each line relay and selectively responsive to the codes transmitted over the line circuit. One form of remote control system operating in the manner thusl far described is 4disclosed and claimed in an application for Letters Patent of the United States, Serial No. 373,675, iiled by L. V. Lewis, on June 25, 1929, for Remote controlling l apparatus. Systems oi this character areparticula-rly suitable for though in no way limited to; use in centralized traic control systems for railroads in which governing devices such as railway switches and signals located adjacent the several line stations are controlled from a train despatchers office and in which the condition of the apparatus at the several stations is indicated ln the despatchers office.

In order to protect the system against line faults, I provide each line relay with a repeater relay designated by the reference character RP with a prex corresponding to the location.y Thus, the relay IRP at station No. 1 is controlled by front contact 2 of relay I R, and the remaining RP relays are controlled 4by corresponding line relays in similar manner. Each station is also provided with a fault relay designated by the reference character F with a suitable prefix and controlled by back contacts of the associated line relay and repeater relay. Referring particularly to station No. 1, the circuit for fault relay IF includes back contact 3 of relay IRP and back contact 4 of relay IR. The repeater relays RP may be slow-acting and the fault relays F are -,constructed to possess a comparatively long time interval so that the interruptions in the line circuit occurring during normal code transmission, do not energize the fault relays. If, however, the line circuit is open for an abnormal period, greater than the longest interval occurring during coding, and such as would occur if a break developed in the line circuit, the fault relays Iall become energized. The fault relay OF at the oice controls an indicator, here shown as a lamp 5, for the purpose of informing the despatche-r of the existence of a break in the line circuit. The normal line circuit may be traced from one terminal of battery N at the ofce, through the winding of the oice line relay OR, and back contact I of the oflice transmitter relay OT, back contact 6 of fault relay IF, winding of line relay IR and back contact I of transmitter relay IT, back contact 6 of fault relay 2F, Winding of line relay 2R, and back contact I of transmitter relay 2T, thence through the remaining stations in similar fashion, returning through the back contacts 'I of the fault relays F at the several stations to the other terminal of battery N. It will be seen from the foregoing that the fault relay at each station has back contacts normally included in the line circuit on the office side of the associated line relay and when the fault relay becomes energized, the line circuit is therefore sectionalized. At the same time, the portion of the line circuit extending from the station to the office is shunted through an auxiliary relay. Referring particularly to station No. 1, when fault relay IF is deenergized, the line circuit is carried over back contacts 6 and 'I of this relay. If, however, the fault relay becomes energized, the line circuit is opened, and auxiliary relay IFR is connected across the line through a back contact 8 of the transmitter relay at this station and a compensating resistance 9. The complete circuit forrelay IFR under these conditions is from one terminal of battery N at the oice, through the winding of relay OR and back contact I of relay OT, front contact 6 of relay IF, back contact 8 of relay IT, resistance 9, winding of relay IFR, and front contact 1 of relay IF, and thence over line wire D2 to the other terminal of battery N. The auxiliary relay IFR is provided with a front contact I0 connected in parallel with contact 6 of relay IF and With a front contact I I connected in parallel with front contact 'I of relay IF. It is manifest, therefore, that when relay IFR is energized, the line circuit is completed through station No. 1 independently of the condition of the fault relay IF. More specically, line wire DI now passes through station No. 1 over front contact ID of relay IFR, winding of relay IR, and back contact I of relay IT; and line wire D2 now passes through station No. l over front contact II of relay IFR. The apparatus located at each way station is similar to that just described in connection with station No. 1.

During normal operation of the system, the back contacts of the fault relays remain closed so that the line circuit is undisturbed by these relays. If a break occurs in the line circuit, however, the line relays will all be deenergized and all the repeater relays RP will also be` deenergized. When the repeater relays release, the fault relays F become energized and, at the conclusion of their time intervals, open their back contacts and close their front contacts. The operation of fault relay OF at the despatchers office lights the lamp 5 and the operation of the fault relays at the stations sectionalize the line circuit at each station. In addition the auxiliary relay IFR at station No. 1 is shunted across the line circuit. If the portion of the line circuit from the despatchers office to station No. 1, is intact, relay IFR becomes energized, thereby continuing the line circuit through station No. 1. If the line circuit is then intact as far as station No. 2, relay 2FR becomes energized in series with line relay IR at station No. 1. The energization of relay IR picks up relay IRP and opens the fault relay IF, thereby deenergizing relay IFR and restoring the normal line circuit as far as station No. 2.

In similar manner the auxiliary relay 2FR at station No. 2 completes the line circuit around the open back contacts of fault relay 2F and the apparatus continues to function as described, stepping through the stations in order until the last station on the oiice side of the break is reached. At this station, the closing of the auxiliary relay FR will nd the line beyond open, so that the line relay at this station will not become energized and the auxiliary relay at the next station will also remain open. For example, if a break occurs between station No. 2 and the next station to the right (not shown), relay 2R will not become energized when relay 2FR picks up. It will be noted that the portion of the line circuit now available includes the usual line relay and contact I of the transmitter relay at the oiiice, and also at station No. 1, but that at station No. 2 it includes the auxiliary relay 2FR and contact 8 of transmitter relay 2T. As shown in Fig. 3, each auxiliary relay such as relay 2FR has a contact I6 connected in series with the line relay contact normally used to control the receiving apparatus, so that when relay 2FR is included in the line circuit and relay 2R is deenergized, relay 2FR may control the receiving apparatus in lieu of relay 2R and in the same manner. It follows, therefore, that the system can now be operated between the ofce and station No. 2 in the usual manner.

If the break in the line circuit is repaired, the system will immediately step through from the last station on the office side of the break to the end of the line circuit, thus automatically restoring the apparatus to its normal condition.

In the remote control system disclosed in the Lewis application hereinbefore referred to, the initiation of each distinctive code is effected by the closing of an individual starting circuit at the sending station by the operation of a code determining relay such as relay ITK or relay IAK of Fig. 3 of the said application, and means are provided for opening the starting circuit automatically to prevent repetition of the code. In order to indicate at the dispatchers oice an approximate location of a line break, I propose to employ my fault relay F at each station as a code determining relay in the manner disclosed in the hereinbefore mentioned Baughman application, and to control the associated starting circuit for the code transmitter at each station not only by the fault relay but also by a front contact I5 of the corresponding auxiliary relay FR,

so that the lastfstation on the oillceA sidev of a break will transmit a distinctive code to the dispatchers oiiice when the line from the oflice to that station is restored. I also propose to provide the dispatchers oflice with receivingl apparatus selectively responsive to each such code to indicate its point of origin.

The initiation or this distinctive code is accomplished by providing at each station the starting circuit illustrated in Fig. 4, which is controlled by the fault relay and by a disagreement relay FD corresponding to the Lewis relay ITD or IAD, for operatingthe associated master relay M of Lewis to initiate the normal code transmission from the corresponding station. For example, if the fault relay F at station No. l should become energized and thereby succeed in closing a portion of the line circuit after a break, current would flow from terminal B over front contact I8 cf relay F, front contact I5 of relay FR and back contact I'I of relay FD, through the Winding of relay M to terminal C. The master relay M would then become energized, thereby operating, as described in the Lewis application, to transmit from station No. 1 a distinctive code. The code thus sent out Would include an impulse indicating the fact that relay F at station No. l was energized and would thus be different from the codes ordinarily employed for transmitting indications to the dispatchers office. It Will be apparent from the foregoing that in apparatus embodying my invention, the fault relays at all stations are operated to sectionalize the line in response to a break in the line circuit and that the apparatus at the several stations then becomes effective to restore the line circuit through the several 'stations in order, commencing at the station nearest the oflice and continuing through all stations up to the last station on the oice side of the break. At this last station, since the line circuit can not be completed to the next station, the line relay remains deenergized, the fault relay remains energized, and the auxiliary relay is held up to permit normal operation of the complete system from this point to the oice.

The fault relays F may be slow-acting relays of any well known form and in order to obtain the desirable time characteristics a thermal relay may be controlled by the associated line relay and repeater relay as shown in Fig. 2. Referring to this view', a thermal relay TH is controlled by a back contact II of the associated line relay R, a back contact I2 of the associated relay RP, and a back contact I3 of the associated fault relay F. With this arrangement, when the line relay is open for a time interval su'icient to drop the line repeater relay RP, current is supplied to the heating element of the thermal relay TH. At the expiration of a time interval, contact Ill of relay TH closes, thereby energizing relay F. The opening of back contact I3 of relay F breaks the heating circuit for relay TH but relay F is subsequently stuck up over its own front contact I3. The relay F, shown in Fig. 2, may be employed to control the line circuit in the same way as the slow-acting relays IF, shown in Fig. 1. Any other form of slow-acting device could be substituted for the fault relays.

Although I have herein shown and described only two forms of apparatus embodying my invention, it is understood that various changes and modifications may be made therein within the scope of the appended claims Without departing from the spirit and scope of my invention.

Having thus described my invention, what I claim is:

l. In a remote control system comprising an oiice and a normally energized line circuit extending irom said oiiice through a plurality of stations, a line relay at each station included in said line circuit, a slow-acting fault relay at each station controlled by a back contact of the associated line relay and having' a back contact included in the line circuit between the associated line relay and the office, an auxiliary relay at each station provided with a circuit including a iront contact oi the associated fault relay and the portion of the line circuit which extends from the olice to the corresponding station, and means eiiective when any auxiliary relay is en.- ergized to bridge said back contact of the associated fault relay to thereby extend said line circuit portion to the next station.

2. In a remote control system, an oflice and a plurality of stations, a line circuit including a source of current and a line relay at the oi'ce and a line relay at each station, a transmitter Contact for briefly interrupting said line circuit, a normally closed sectionalizing contact at each station in said line circuit, means responsive only to a prolonged interruption oi said line circuit to close a shunt at each static-n to complete a circuit for said source when the line circuit from the oflice to such station is intact and to open said contacts to thereby sectionalize the line circuit at each station so that but one such circuit will be closed at a time, restoring means at each l station responsive to the office source oi current and rendered effective when said contact opens provided the portion of the line circuit from the oice to that station is intact to extend said portion to the next station, and means controlled f.

by each restoring means when energized responsive to the flow oi current in such extended portion to open said shunt and to close said contact at such station.

3. In a remote control system, an cnice and L a plurality of stations connected by a line circuit including a source of energy at the orlice, a normally energized line relay at each station in said line circuit, a transmitter contalctl for briey opening the line circuit to deenergize said line relays, normally inactive means at each station responsive only to a prolonged deenergization of the line relay at such station for opening the portion of the line circuit including said line relay and leading to the next station and for shunting said portion to permit the portion of the line circuit leading from the office to such station to become closed, and means responsive to the energization of the portion of the line circuit leading from the oce to such station for effecting the reenergization of the line relay pro-vided the portion of the line circuit leading to the next succeeding station is 'intact to automatically restore said normally inactive means to its original condition.

4. In a remote control system, an oflice and a plurality of stations, a normally energized line circuit extending from the oiiice serially through said stations including a source of current at the office, sectionalizing means at each station responsive to a break in said line circuit to close a shunt to complete a circuit for said source when the line circuit is intact from the cnice to such station, and to interrupt the portion of the line circuit extending from such station to the next succeeding station so that but one such circuit will be closed at a time, restoring means at each station responsive to current from said source included in the shunt at such station for restoring the line circuit through such station, and means controlled by each restoring means when energized responsive to the flow of current in the portion of the line circuit leading to the next succeeding station for restoring the associated sectionalizing means.

5. In a remote control system comprising an oiiice and a line circuit extending from said office through a plurality of stations, a fault relay at each station having a normally closed contact included in said line circuit, means responsive to a breal; 1'n said line circuit to operate all said fault relays to open said contacts, to thereby sectionalizc the line circuit at each station, a shunt at each station closed when the fault relay at such station operates to complete a circuit including the portion of the line circuit leading from the office to such station if such portion. is intact, a restoring relay at each station included in the shunt at such station having a front contact bridging said fault relay contact to restore the line circuit through such station when the restoring relay is energized, and a line relay at each station included in the portion of the line circuit leading to the next succeeding station elective when energized to restore the fault relay at such station to its original condition.

6. In a remote control system, an office and a plurality of stations, a normally energized line circuit extending from said office serially through said stations, a fault relay at each station, means energizing each fault relay response to a break in said line circuit, an auxiliary relay at cach station, means energizing each auxiliary relay when the fault relay at the same station is energized provided the portion oi the line circuit extending r" the oice to such station is closed mainder ci the line circuit is open,

cuit and controlled by the fault relay and by the associated auxiliary relay respectively at such station for opening the portion of the line circuit leading to the next succeeding station when the fault relay becomes energized and for restoring said. line circuit portion when the auxiliary relay becomes energized, a plurality of line relays including one at each station, means energizing the line relay at each station when the line circuit from the office through such station to the next succeeding station is closed, and means controlled by each line relay when energized for releasing the associated fault relay.

I'l'. In a remote control system comprising an oiice and a normally energized line circuit extending from said oflice through a plurality of stations, an auxiliary relay at each station, a fault relay at each station having a back contact included in said line circuit, a shunt at each station to complete the portion of the line circuit leading to the oice including the auxiliary relay and a front contact of the fault relay, means responsive to a break in said line circuit to energize all said fault relays, means effective when each auxiliary relay becomes energized to shunt said baci: contact of the corresponding fault relay, and means at each station included in the portion of the line circuit leading from such station to the next succeeding station effective to deenergize the corresponding fault relay provided said last named line circuit portion is intact.

8. In a remote control system, an oiiice and a plurality of stations, a normally energized line circuit extending from the oice serially through said stations including a source of current at the omce, sectionalizing means at each station responsive to a break in said line circuit to close a shunt to complete a circuit for said source when the line circuit is intact from the ofiice to such station, restoring means at each station rendered responsive to current from said source when the shunt at such station is closed, means controlled by each restoring means when energized responsive to the iioW of current in the portion of the for releasing the associated sectionalizing means, to serially open the shunts at the stations between the silice and the last station on the oiiice side of the break, and a transmitter starting contact at each station controlled by the restoring means at such station for indicating when such restoring means is operated.

JOI-IN M. PELIKAN.

Lne circuit leading to the next succeeding station l 

